Debt and Interest Expense - Debt Activity Table (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 3,492,712
Other	(18,366)
Ending balance	4,204,346
Western Gas Partners, LP [Member] \| Revolving Credit Facility [Member] \| WES RCF [Member]
Changes in Debt Outstanding [Roll Forward]
RCF borrowings	260,000
Repayments of RCF borrowings	(630,000)
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 4.500% Senior Notes due 2028 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	400,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.300% Senior Notes due 2048 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	$ 700,000

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

No definition available.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Changes in Debt Outstanding [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Represents debt issuance costs, including but not limited to legal, accounting, underwriting, printing and registration costs for debt issuances during the year, in addition to amortization of expense attributable to debt discount (premium) and debt issuance costs.

+ References

No definition available.

+ Details

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